Module 1, Lecture 1 & 2 Flashcards
What is a toxin?
A poison that originates from biological processes.
What is an example of a toxin?
- Mycotoxin
- Biotoxin
- Algae (phycotoxins)
- Plants (phytotoxins)
What is a poison?
Any solid, liquid, or gas that when introduced into a biological system interferes with the life processes of the cells of that organism.
What is a toxicant?
Less harsh version of a poison (feed additive, drug, etc.)
What is toxicosis?
The disease state of being poisoned
What is toxicity?
The quantity or amount of a toxicant that under a certain set of conditions will cause adverse effects.
How is toxicity often expressed?
mg toxicant / kg body weight
What is the LD50?
Lethal dose 50 : the dose that will KILL 50% of the population.
What is the ED50?
Effective dose 50 : the dose required to produce a specific effect in 50% of the population.
What is the NOEL?
No-observed-effect-level : An exposure level at which there are no statistically or biologically significant increases in the frequency or severity of any effect between the exposed population and its appropriate control.
What is the NOAEL?
No-observed-adverse-effect-level : highest dose that has been reported to have NO harmful (adverse) effects.
What is the HNTD?
Highest non-toxic dose
What is the MLD?
Minimum lethal dose
Which factor determines the response to a toxin?
Dosage (determines the concentration at the target site)
What is an acute response?
< 7 days
What is a subacute response?
< 30 days
What is a subchronic response?
< 90 days
What is a chronic response?
> / = 90 days
Mean +/- 1 standard deviation = ____% of the population.
68.3%
Mean +/- 2 standard deviations = ____% of the population.
95.5%
Mean +/- 3 standard deviations = ____% of the population.
99.7%
What is the equation for the therapeutic index?
LD50 / ED50
What is the equation for the standard safety margin?
LD50 / ED99
What is the equation for the chronicity factor?
Acute LD50 / 90-day LD50
What is the equation for risk ratio?
Use level / toxic level
